How I 3D Printed My Own Lego-Compatible Train Bridges

March 16, 2026 by Lewin Day 38 Comments

Lego train sets have been available for decades, now. The Danish manufacturer long ago realized the magic of combining its building block sets with motors and plastic rails to create real working railways for children and adults to enjoy. Over the years, Lego has innovated through several generations of trains, from classic metal-rail systems to the more modern IR and later Bluetooth-controlled versions. The only thing largely missing over all that time, though…? A bridge!

Yes, Lego has largely neglected to build any bridges for its mainstream train lineup. There are aftermarket solutions, and innovative hacks invented by the community, all with their own limitations and drawbacks. This glaring oversight, though, seemed like a perfect opportunity to me. It was time to fire up the 3D printer and churn out a fully-realized Lego rail bridge of my very own.

Bridges Are Hard

I’ve experimented with building Lego rail bridges before, using standard track and household objects like cardboard, books, and beer. Unfortunately, it can be very difficult to support the track evenly at the joints which occur every 150mm, and derailments are common. Credit: author

There’s actually a good reason Lego bridges aren’t a big thing in the company’s own product lineup, beyond a few obscure historical parts. This is probably because they aren’t very practical. Lego locomotives are not particularly strong haulers, nor do they have excellent grip on the rails, and this makes them very poor at climbing even mild grades. Any official Lego bridge would have to be very long with a shallow slope just to allow a train to climb high enough to clear a locomotive on a track below. This would end up being an expensive set that would probably prove unpopular with the casual Lego train builder, even if the diehard enthusiasts loved it.

There are third-party options available out there. However, most rely on standard Lego track pieces and merely combine them with supports that hold them up at height. This can work in some cases, but it can be very difficult to do cool things like passing a Lego train under a bridge, for example. It can be hard to gain enough height, and the short length of Lego track pieces makes it hard to squeeze a locomotive between supports. Continue reading “How I 3D Printed My Own Lego-Compatible Train Bridges” →

Ask Hackaday: Wired Or Wireless Headphones?

March 16, 2026 by Al Williams 71 Comments

They say you should never throw out old clothes because they will come back in style one day. Maybe they are right. We noted in a recent BBC post that, apparently, wired headphones are making a comeback. Like many people, we were dismayed when Apple took the headphone jack out of the iPhone and, as [Thomas Germain] notes, even Google eventually ejected the normal headphone jack. (Although, in fairness, most of the Pixel phones we’ve seen come with a pair of USB-C earbuds.)

On the face of it, though, wireless seems to be a good idea. You can get cheap Bluetooth earbuds now, although maybe still not as cheap as wired buds. Sure, they sound terrible, but so do cheap buds. It is a pain to charge them, of course, but not having to untangle wires is a benefit. On the other hand, you never have to charge your wired headphones.

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Hackaday Links: March 15, 2026

March 15, 2026 by Tom Nardi 4 Comments

Some days, it feels like we’re getting all the bad parts of cyberpunk and none of the cool stuff. Megacorps and cyber warfare? Check. Flying cars and holograms? Not quite yet. This week, things took a further turn for the dystopian with the news that a woman was hospitalized after an altercation with a humanoid robot in Macau. Police arrived on scene, took the bot into custody, and later told the media they believed this was the first time Chinese authorities had been called to intervene between a robot and a human.

The woman, reportedly in her seventies, was apparently shocked when she realized the robot was standing behind her. After the dust settled, the police determined it was being operated remotely as part of a promotion for a local business. We’ve heard there’s no such thing as bad publicity, but we’re not sure the maxim holds true when you manage to put an old lady into the hospital with your ad campaign.

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What Is A Computer?

March 14, 2026 by Elliot Williams 36 Comments

On the podcast, [Tom] and I were talking about the new generation of smartphones which are, at least in terms of RAM and CPU speed, on par with a decent laptop computer. If so, why not just add on a screen, keyboard, and mouse and use it as your daily driver? That was the question posed by [ETA Prime] in a video essay and attempt to do so.

Our consensus was that it’s the Android operating system holding it back. Some of the applications you might want to run just aren’t there, and on the open side of the world, even more are missing. Is the platform usable if you can’t get the software you need to get your work done?

But that’s just the computer-as-a-tool side of the equation. The other thing a computer is, at least to many of our kind of folk, is a playground. It’s a machine for experimenting with, and for having fun just messing around. Android has become way too polished to have fun, and recent changes on the Google side of things actively prevent you from installing arbitrary software. The hardware is similarly too slimmed-down to allow for experimentation.

Looking back, these have been the same stumbling blocks for the last decade. In 2018, I was wondering aloud why we as a community don’t hack on cell phones, and the answer then was the same as it is now – the software is not friendly to our kind. You can write phone apps, and I have tried to do so, but it’s just not fun.

The polar opposites of the smartphone-as-computer are no strangers in our community. I’m thinking of the Linux single-board computers, or even something like a Steam Deck, all of which are significantly less powerful spec-wise than a flagship cell phone, but which are in many ways much more suitable for hacking. Why? Because they make it easy to do the things that we like to do. They’re designed to be fun computers, and so we use them.

So for me, a smartphone isn’t a computer, but oddly enough it’s not because of the hardware. It’s because what I want out of a computer is more than Turing completeness. What I want is the fun and the freedom of computering.

German Fireball’s 15 Minutes Of Fame

March 11, 2026 by Elliot Williams 20 Comments

Sunday night, around 7:00 PM local time, a bright fireball streaked across the western German sky, exploded, and rained chunks of space rock down on the region around Koblenz. One of the largest known chunks put a soccer-ball-sized hole in someone’s roof, landing in their bedroom. Fortunately, nobody was hurt. But given the apparent size of the explosion, there must be many more pieces out there for the finding, and a wave of hopeful meteorite hunters has descended upon the region.

But if you wanted a piece of the action, where exactly would you start looking? How do scientists find meteorites anyway? And what should you do if you happen to see a similar fireball in the night sky?

Citizen Science

Meteorite video-bombs a boring parking lot in Heerlen, NL.

In the age of always-on dashboard cameras, ubiquitous smartphones, and other video recording devices, it’s hard for a shy meteorite to find a quiet spot out of the public eye. That makes them a lot easier to find than they were in the past. Indeed, the International Meteor Organization, which aggregates amateur meteor observations, received more than 3,200 reports of this one, including several with video documentation. Some are stunning, and others may not even be of the event at all.

By collecting reports from many locations, they can hope to piece together the meteorite’s trajectory. However, if you look at the individual reports, it’s clear that this is a difficult task. Nobody is expecting a bright fireball to streak across the night sky, so many of the reports are reasonably vague on the details and heavy on the awe.

This report from [Sophie Z], for instance, is typical. She records where she was and roughly the location in the night sky where the meteorite passed, along with the comment “I’ve never seen anything so amazing and large before in my life.” Other amateur observers are more precise. [David C] (“I have a Ph.D in physics”) managed to record the start and the end heading of the meteorite to a couple of decimal places. He must have had a camera.

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The “Tin Blimp” Was A Neither Tin Nor A Blimp: The Detroit ZMC-2 Story

March 10, 2026 by Tyler August 31 Comments

That fireball was LZ37. Nobody wanted to see repeats post-war.
Image: “The great exploit of lieutenant Warnefort 1916 England” by Gordon Crosby, public domain.

After all the crashing and burning of Imperial Germany’s Zeppelins in the later part of WWI – once the Brits managed to build interceptors that could hit their lofty altitude, and figured out the trick of using incendiary rounds to set off the hydrogen lift gas – there was a certain desire in airship circles to avoid fires. In the USA, that mostly took the form of replacing hydrogen with helium. Sure, it didn’t lift quite as well, but it also didn’t explode.

Still, supplies of helium were– and are– very much limited, and at least on a rigid Zeppelin, the hydrogen wasn’t even the most flammable part. As has become widely known, thanks in large part to the Mythbusters episode about the Hindenburg disaster, the doped cotton skin in use in those days was more flammable than some firestarters you can buy these days.

That’s a problem, because, as came up in the comments of our last airship article, rigid airships beat blimps largely on Rule of Cool. Who invented the blimp? Well, arguably it was Henri Griffard with his steam-driven balloon in 1857, but not many people have ever heard his name. Who invented the rigid airship? You know his name: Ferdinand Adolf Heinrich August Graf von Zeppelin. No relation. Probably. Well, admittedly most people don’t know the full name, but Count Zeppelin is still practically a household name over a century after his death. His invention was just that much cooler.

That unavoidable draw of coolness led to the Detroit Airship Company and their amazing tin blimp. The idea was the brainchild of a man named Ralph Upton, and is startling in its simplicity: why not take the all-metal, monocoque design that was just then being so successfully applied to heavier-than-air flight, and use it to build an airship? Continue reading “The “Tin Blimp” Was A Neither Tin Nor A Blimp: The Detroit ZMC-2 Story” →

Ask Hackaday: What Will An LLM Be Good For In The Plateau Of Productivity?

March 9, 2026 by Jenny List 73 Comments

A friend of mine has been a software developer for most of the last five decades, and has worked with everything from 1960s mainframes to the machines of today. She recently tried AI coding tools to see what all the fuss is about, as a helper to her extensive coding experience rather than as a zero-work vibe coding tool. Her reaction stuck with me; she referenced her grandfather who had been born in rural America in the closing years of the nineteenth century, and recalled him describing the first time he saw an automobile.

Après Nous, Le Krach

The Gartner hype cycle graph. Jeremykemp, CC BY-SA 3.0.

We are living amid a wave of AI slop and unreasonable hype so it’s an easy win to dunk on LLMs, but as the whole thing climbs towards the peak of inflated expectations on the Gartner hype cycle perhaps it’s time to look forward. The current AI hype is inevitably going to crash and burn, but what comes afterwards? The long tail of the plateau of productivity will contain those applications in which LLMs are a success, but what will they be? We have yet to hack together a working crystal ball, but perhaps it’s still time to gaze into the future. Continue reading “Ask Hackaday: What Will An LLM Be Good For In The Plateau Of Productivity?” →